Meet LUCA, the planetary mega-organism

There is a new interesting idea for the early evolution of life on Earth. According to this view, the Last Universal Common Ancestor (LUCA) of all life forms today can be traced back 3 billion years (hence not back to the origin of life). This common ancestor was a single mega-organism that filled the oceans. 2.9 billion years ago it split into three and gave birth to the ancestors of all living beings that we know: single-celled bacteria, archaea, and complex eukaryotes (from where animals and plants have emerged). Read more here.